Gas turbine engines generally include a turbine section downstream of a combustion section that is rotatable with a compressor section to rotate and operate the gas turbine engine to generate power, such as propulsive thrust. General gas turbine engine design criteria often include conflicting criteria that must be balanced or compromised, including increasing fuel efficiency, operational efficiency, and/or power output while maintaining or reducing weight, part count, and/or packaging (i.e. axial and/or radial dimensions of the engine).
Within at least certain gas turbine engines, the turbine section may include interdigitated rotors (i.e., successive rows or stages of rotating airfoils or blades). For example, a turbine section may include a turbine having a first plurality of low speed turbine rotor blades and a second plurality of high speed turbine rotor blades. The first plurality of low speed turbine rotor blades may be interdigitated with the second plurality of high speed turbine rotor blades. Such a configuration may result in a more efficient turbine.
However, several problems may arise with such a configuration relating to unwanted vibrations (e.g., vibration modes), clearance issues between the first and second pluralities of rotor blades, etc. Accordingly, an improved turbine with interdigitated turbine rotor blades would be useful.